On Wednesday, I wrote about a battle looming between Apple and Googleas discussions take place over the possibility of Apple making Microsoft‘s Bing the default search engine on the iPhone.

Stepping back further than a single search engine fight, it’s evident that Google, Microsoft, Apple, and even Yahoo are now competing in numerous different business arenas.

The chart above illustrates many of the services these companies provide. Some of their products have been cornerstone revenue streams, and others are just at the beginning of development. But putting them up against each other really helps illustrate each company’s focus and their possible future directions of exploration.